Method for producing AlMn strips or sheets

Abstract

The present invention relates to a method for producing AlMn strips or sheets for producing components by soldering, wherein a precursor material is produced from a melt which contains (in weight-percent) Si: 0.3-1.2%, Fe: ≦0.5%, Cu: ≦0.1%, Mn: 1.0-1.8%, Mg: ≦0.3%, Cr+Zr: 0.05-0.4%, Zn: ≦0.1% , Ti: ≦0.1% , Sn: ≦0.15%, and unavoidable companion elements, whose individual amounts are at most 0.05% and whose sum is at most 0.15%, as well as aluminum as the remainder, wherein the precursor material is preheated at a preheating temperature of less than 520° C. over a dwell time of at most 12 hours, wherein the preheated precursor material is hot rolled into a hot strip using a final hot rolling temperature of at least 250° C., wherein the hot strip is cold rolled into a cold strip without intermediate annealing.

What is claimed is:  
     
       1. A method for producing an AlMn strip or sheet for producing a component by soldering, said method comprising: 
       producing a precursor material from a melt, said melt comprising (by weight):  
       0.3 to 1.2% Si;  
       not more than 0.5% Fe;  
       not more than 0.1% Cu;  
       1.0 to 1.8% Mn;  
       not more than 0.3% Mg;  
       a sum of Cr and Zr in the range 0.05 to 0.4%;  
       not more than 0.1% Zn;  
       not more than 0.1% Ti;  
       not more than 0.15% Sn;  
       unavoidable companion elements; and aluminum as the remainder;  
       wherein any one of said unavoidable companion elements individually amounts to at most 0.05%; and all of said unavoidable companion elements collectively amount to at most 0.15%; and wherein the ratio of weight percent Sn to weight percent Si is not less than 0.03;  
       preheating said precursor material at a preheating temperature of less than 520° C. over a dwell time of at most 12 hours;  
       hot rolling said precursor material to produce a hot-rolled strip, said hot rolling comprising a final hot rolling at a temperature of at least 250° C.; and  
       cold rolling said hot-rolled strip to produce a cold-rolled strip or sheet without intermediate annealing.  
     
     
       2. The method according to  claim 1  wherein the ratio of weight percent Sn to weight percent Si is not less than 0.1. 
     
     
       3. The method according to  claim 1  or  2  wherein said melt comprises, by weight, at least 0.5% Si. 
     
     
       4. The method according to  claim 1  or  2  wherein said melt comprises, by weight, at least 0.75% Si. 
     
     
       5. The method according to  claim 1  wherein said melt comprises, by weight, at most 1.0% Si. 
     
     
       6. The method according to  claim 1  wherein said melt comprises, by weight, at most 0.3% Fe. 
     
     
       7. The method according to  claim 1  wherein said melt comprises, by weight, at most 0.05% Cu. 
     
     
       8. The method according to  claim 1  wherein said melt comprises, by weight: 
       at least 1.3% Mn; and  
       at most 1.5% Mn.  
     
     
       9. The method according to  claim 1  wherein said melt comprises, by weight, at most 0.1% Mg. 
     
     
       10. The method according to  claim 1  wherein said melt comprises, by weight; 
       at least 0.1% Cr; and  
       at most 0.2% Cr.  
     
     
       11. The method according to  claim 1  wherein said melt comprises, by weight, at most 0.05% Zr. 
     
     
       12. The method according to  claim 1  wherein said melt comprises, by weight, at most 0.05% Zn. 
     
     
       13. The method according to  claim 1  wherein said melt comprises, by weight, at most 0.05% Ti. 
     
     
       14. The method according to  claim 1  wherein said AlMn strip or sheet after soldering comprises a limit of elasticity R P0.2  of at least 60 Mpa. 
     
     
       15. The method according to  claim 14  wherein said limit is at least 65 Mpa. 
     
     
       16. The method according to  claim 1  wherein said producing comprises continuously casting ingots from said melt. 
     
     
       17. The method according to  claim 1  wherein said preheating temperature is at most 470° C. 
     
     
       18. The method according to  claim 1  wherein said preheating temperature is at least 400° C. 
     
     
       19. The method according to  claim 1  wherein said dwell time is at most 5 hours. 
     
     
       20. The method according to  claim 1  wherein said hot rolling comprises hot rolling said precursor material into a hot-rolled strip having a thickness that is in the range of 2 to 10 mm. 
     
     
       21. The method according to  claim 1  wherein said final hot rolling is at a temperature of at least 250° C. 
     
     
       22. The method according to  claim 1  wherein said final hot rolling is at a temperature of at least 300° C. 
     
     
       23. The method according to  claim 1  further comprising subjecting said cold-rolled strip or sheet to an annealing treatment. 
     
     
       24. The method according to  claim 23  wherein said subjecting comprises annealing said cold-rolled strip or sheet in a coil. 
     
     
       25. The method according to  claim 23  wherein said subjecting comprises annealing said cold-rolled strip or sheet in a continuous furnace. 
     
     
       26. The method according to  claim 23  wherein the temperature of said cold-rolled strip or sheet is at least 300° C. during said annealing treatment. 
     
     
       27. The method according to  claim 23  wherein the temperature of said cold-rolled strip or sheet is at least 350° C. during said annealing treatment. 
     
     
       28. The method according to  claim 1  wherein said cold rolling comprises cold rolling said hot-rolled strip into a cold-rolled strip or sheet having a thickness that is between 50 μm and 500 μm. 
     
     
       29. The method according to  claim 1  further comprising, when said cold-rolled strip or sheet comprises a first side and a second side, applying a first cladding layer to at least one of said sides; 
       wherein:  
       the sum of thicknesses of (1) cladding layers applied in said applying, and (2) said strip or sheet defines a total thickness; and  
       the thickness of said first cladding layer is from 3% to 20% of said total thickness.  
     
     
       30. The method according to  claim 29  wherein said applying comprises: 
       applying said first cladding layer to one of said sides, said first cladding layer comprising a first aluminum alloy; and  
       applying a second cladding layer to another of said sides, said second cladding layer comprising a second aluminum alloy;  
       wherein the thickness of said second cladding layer is from 3% to 20% of said total thickness.  
     
     
       31. The method according to  claim 30  wherein both of said applyings comprise using hot roll cladding. 
     
     
       32. An AlMn strip or sheet produced according to the method of  claim 1 . 
     
     
       33. The AlMn strip or sheet of  claim 32  wherein said AlMn strip or sheet after soldering comprises a limit of elasticity R P0.2  of at least 60 Mpa. 
     
     
       34. The AlMn strip or sheet of  claim 32  wherein the limit of elasticity R P0.2  of said AlMn strip or sheet after soldering is at least 65 Mpa.